Conventional switching platforms are advantageously employed in telecommunications systems to facilitate, for instance, private branch exchange (PBX) administered interoffice communications or switching and call queuing functionality for a call center. Call centers are employed in a multitude of applications such as telemarketing, customer service and sales support applications. A call center is typically embodied in a central location wherein inbound and outbound calls are processed by an organization in association with computer automation. The call center generally employs a number of agents who communicate with customers via telephone, facsimile, electronic mail, or other communication techniques or devices. The call center has the ability to handle a considerable volume of communication traffic at the same time in association with automation techniques such as call routing and equitable distribution, call screening, agent skill matching, and other resource optimization and management reporting functionality.
A switching platform employable with a call center typically includes a computer server system that provides call and control processing functions for the call center. The computer server system may employ a number of input-output distributor (IOD) cards connectable via a multibus interface. Each IOD card provides an interface from a main control unit (MCU) to a switching matrix, which is capable of controlling a number of line cards. The line cards provide the physical interface to access nodes, which may include digital and analog instruments and digital and analog trunks.
The switching platforms generally employ a hub and spoke topology wherein the computer server system (the hub) distributes communication traffic to a number of switching matrices (the spokes) at a number of sites. The distribution capability of the switching platform enables overflow traffic from one site to be distributed to other sites as needed.
The hub and spoke topology, however, suffers from a number of deficiencies. More specifically, the computer server system must be located proximate to the IODs due to the limited distance capability of the multibus interface. Moreover, for reasons that will become more apparent, the hub and spoke topology does not readily address the continuing availability of the unified switching platform should the centralized hub site experience a failure.
Inasmuch as call centers represent a significant investment in advancing the quality of the customer interface with a business and in providing connectivity for a source of revenue for the business, it is essential that the call centers be highly fault tolerant. In an attempt to address the aforementioned predicament, the computer server system of the switching platform employed with most call centers generally includes primary and secondary controllers, referred to as a redundant pair of master control units (MCUs).
Typically, the MCUs are tightly connected by proprietary intermachine communication methods and protocols to ensure that one of the controllers operates as the primary controller (or in the master mode) and the other controller acts as the secondary controller (or in the standby mode). The secondary controller assumes control of the call center in the event that the primary controller experiences difficulty. Although the MCUs can interchange roles, it is common to designate one of the controllers as the primary controller for a given period of time.
While the redundant pair of MCUs affords a degree of fault tolerance, the system suffers from a few limitations. First, restrictions associated with the intermachine data communication methods and protocols (including operational data synchronization) makes it necessary to locate the redundant pair of MCUs within close proximity to one another. Of course, locating the MCUs in close proximity detracts from the fault tolerance ability of the system. Another limitation associated with the system is that the MCUs also should be located in close proximity to the other major components of the switching platform due, in part, to the communications system architecture associated with the MCUs. Thus, the hub-based design of the switching platform cannot accommodate a truly distributed architecture (whereby the integrity of the telecommunications system is not dependent on the operation of a centralized site or hub) thereby further limiting the fault tolerant nature thereof.
Accordingly, what is needed in the art is a switching platform that overcomes the deficiencies of the prior art.